doublegunshop.com - home Forums General Discussion DoubleGun BBS @ doublegunshop.com Parker with 2 3/4" chambers

Anyone know when Parker went to 2 3/4" chambers in 12 ga?

Parker Bros. had the policy of holding their chambers 1/8 inch shorter than the intended shell. Hence most Parker Bros. 12-gauge doubles were intended by the makers for 2 3/4 inch shells even though the chambers are in fact 2 5/8 inch. Even the Remington era Parker specification sheets call for these 1/8 inch shorter chambers. In theory if a 12-gauge Parker Bros. double left Meriden with 2 3/4 inch chambers it would have been intended for 2 7/8 inch shells.

The theory behind this, as explained in an American Rifleman article from the 30's, is that the case mouth would open just into the forcing cone and provide some protection to the shot on its initial contact with the barrels. Tests showed improved patterns with slightly longer shells in shorter chambers. Plastic wads have pretty much rendered that benefit obsolete.

I assume it these guns were intended for role turn over cases not crimped.

Odd that practice was not extended to the 10ga, whether square shouldered or tapered they measure 2 7/8" for 2 7/8".

The Parker Brothers chamber blueprints include ten gauge as well as smaller gauges to be 1/8" shorter than the shell. Individual guns can measure any length under the sun. Only factory paperwork can prove the intent. Parker blueprints and hang tags prove the intent. Most hang tags show only chamber length. Some hang tags show chamber length and intended shell to be 1/8" different.

how about an answer to gunmans question about roll or reg. crimp and chamber length?

2 3/4" fold crimps came into general use long before Parker closed their doors. 2 3/4" fold crimp and roll crimp hulls have the same length.

The Super-Seal Crimp first appears in the 1940 Western Ammunition Handbook, and in the 1941 Winchester Ammunition Guide. Through at least 1938, Remington was still using the roll crimp. The next Remington ammunition paper I have is 1949 and it is touting the "New Remington Crimp." So, damn few Parker doubles were ever built with anything but a roll crimp in mind.

The type of crimp should not make any difference, as long as the fired hull is the same length--as Joe stated. There will be a slight increase in pressure as a result, which was understood even back in the 30's when the practice of slightly longer shells in shorter chambers was fairly common. But that increase was not enough to exceed the pressure parameters for which the guns in question were built to handle.

Note they have the same fired length, not the same loaded length. The loaded length of the fold crimp shell will be shorter than that of the roll crimp as more paper/plastic is used in the crimp.

Firing a shell longer than the chamber is actually more critical for the roll crimp than the folded one. "IF" the end of the loaded shell is actually pushed into the forcing cone this can increase the force necessary to open the crimp, which can result in a drastic rise in chanber pressure.

I would guess that 1/8" used by Parker to be about the max amount for a roll crimped hull while a little more would likely be acceptable for a fold crimp.

Wouldn't it be easier to just say nothing or I don't know ?

I did my informal proof test and the gun didn't come apart with 2 3/4" shells.

Not to say it won't come apart in the future.

Gee Joe . . . I thought the question had already been answered. But there's definitely more to be said about manufacturers intentionally short-chambering their guns, even if marked 2 3/4". I've got the American Rifleman articles from the 1930's, written by Arthur Curtis, who'd worked in the firearms industry for about 40 years. What seems to have been common knowledge (and practice) back then is not so commonly known today.

One of these days, you're actually going to add something of substance to a discussion . . . and many doublegunshop regulars will undoubtedly go into a state of shock as a result.

Only reason I ever read your posts is so I can watch Miller set you straight.

Genelang,

I measured my Parker 12Ga VHE Remington Era shotgun, made in June 1939, using a Galazan chamber length gauge and a Mitutoyo micrometer. The chambers depth is 2.6875, right half way between 2 5/8" (2.625) and 2 3/4" (2.750). So by 1939, using only one example, they seemed not totally decided to go for 2 3/4in chambers yet.

Regards,

EJSXS

Well, that's better than no reason at all to read yours--unless one is short on BS for the day.

My gun was made in 1891. It's a heavy No 2 frame, probably a duck gun originally. I can't find any stats except that Parker didn't feel obliged to conform to standard length chambbers.

Gunsmith Roy Dunlap in his book "Gunsmithing" gives chamber dimensions for the 12, 16 & 20 gauges for 2 3/4" shells & the .410 & 20ga for 3" shells. Copyright for this book is 1950 & 1963. The 3" 20 is in an appendix of 1963.
The 2 3/4" 16 & 20 gauges call for minimum chamber depths of 2 3/4", the 3" .410 for min depth of 3.000".
The 3" 20 ga lists a minimum chamber depth of 2.880" & minimum cone of 5� per side.
The 2 3/4" 12 ga lists a minimum chamber length of 2.6136" also with a minimum cone angle of 5� per side. Note that this minimum cone from a minimum chamber dia of .798" to a standard bore of .729" would give a cone length of .394"
Max length for the unfired hull is 2.760", loaded length for a roll crimp hull is 2.53" & for a fold crimp one 2.41".
Shells of either of these "Loaded" lengths will not enter the cone prior to firing, but of course both would after firing assuming the minimum chamber.

Upon introduction of the fold crimp in England due to the possibility of the shorter loaded shells being mistankenly used in a 2" chambered gun the British did extensive testing on this matter of hull length. The outcome was that shells marked for use in the "So Called" 2�" chambers (they were more apt to actually be 2 9/16" or 65mm) were actually of a nominal 2 3/4" in unfired length which made them close to the standard roll crimp loaded length. Burrard gave this extensive coverage in "The Modern Shotgun" still among, if not The, best book on shotguns ever written.
I assume that Dunlap's specs were SAAMI for the day. Most likely the shorter chamber length specified for the 12ga was the result of "Past Practise" & was apparently based on the whims of trap shooters, thus only applied to the 12.

2 thingsa For the Record;
1st, this post is for JOE
2nd, all this was well established before Sherman Bell got out of Diapers, if in fact he was even born yet. His reports may heve been useful to a lot of Folks, but he didn't really "Discover" anything.

Miller, it's not so much a case of discovering anything as it is of bringing to people's attention something discovered far earlier but, unfortunately, largely forgotten. In his two part "Advantages of Short Shotgun Chambers" (American Rifleman, July 1936 and March 1938), Arthur Curtis presented some interesting information on longer shells in short chambers:

"As far back as 1910, the late Harvey McMurchy broke 99 x 100 clay targets from 17 yards at that year's Grand American Handicap, using 3" 12 gauge shells in an L.C. Smith gun chambered for the standard 2 3/4" shell." He adds that back then, Hunter Arms had conducted tests using shells 1/4" longer than the chambers in 20's and 16's as well as 12's. Other trap shooters, based on McMurchy's experience, started using 3" shells in 2 3/4" guns. But those sponsored by many of the gun companies were told to stop the practice, for the simple reason that the longer shells, while fine in doubles, would not work in the pumpguns sold by those companies.

Per Curtis: "The greatest (advantage) lies in the fact that the opening-up of the crimp, in firing, lines the steel forcing cone with soft paper, that re-forms, elongates, and gides the shot charge into the true bore without as great deforming of the pellets as when 2 3/4" shells are used."

As you mentioned, Miller, Burrard discussed the British experience with long shells/short chambers in his book. Yet a couple decades later, there was still sufficient concern among the British shooting public that Gough Thomas repeated the experiment, giving the resulting readings (both pressure and velocity) from a 10-shot string, 2 3/4" shells fired in both 2 1/2" and 2 3/4" chambered pressure guns. There was essentially no change in either pressure or velocity. Bell did the same thing, but with a wide variety of reloads (and even tried 3" shells in a 2 1/2" chamber). What had happened in the interim, between Curtis and Burrard some 70 years ago, and Thomas in the 60's and Bell more currently, was that most people had forgotten the earlier experiments. (Mainly because people kept reading, on shell boxes, the warning not to fire 2 3/4" shells in guns with chambers shorter than that.) And both Thomas and Bell gave actual pressure readings from their tests, which in Bell's case did show some increase (over 1,000 psi in some cases), but not so much that it should cause concern as long as the careful reloader builds in enough of a safety cushion in the loads he produces and uses in short-chambered guns. So while neither one really discovered anything, I think both Thomas' and Bell's tests were valuable as reminders.

I love it when you confuse Brown and he types a half a page of gibberish in response.

So Joe, you knew all that stuff I just posted? Right. I'm not confused in the least. Meanwhile, you have 3 posts this thread, 0 substance. That's 0 for 3. Keep going, Joe, and the manager's going to bench you because you're not hitting. Scratch that . . . if that were the case, you would have been sent back to the minors years ago. In your case, there ought to be a special batting average to score your posts. .000 is way too high.

Larry next time you don't know the answer to the mans question just don't say nothing.

"Just don't say nothing." That's a double negative, Joe . . . and you are now 0 for 4 on substance. One of us has contributed factual information to this thread, and it's not you.

The turn of the century Parker 12ga "Pigeon" gun's were ordered with 2 7/8" chambers.